Hubert Wilhelm Jung was born in Stuttgart in 1883 as the youngest of seven children. After attending secondary school in Ravensburg, he registered in 1904 in the Architecture Department of the University of Technology in Munich.

Adolf Proksch came from a conservative Catholic background. He studied law and until the First World War he worked for the Vienna Siemens-Schuckert-Werke and thereafter for the Ministry of War.

Paul von Zsolnay was born in Budapest in 1895 as the first son of the tobacco industrialist and Austrian consul general Adolf von Zsolnay (1866–1932) and his wife Klara Amanda, called Andy (1876–1956), née Wallerstein.